JDBC memory leak in 11.2.0.2.0 driver ?

Hi,
my customer on WLS 9.2.1 have just upgraded to new database and to a new JDBC Oracle 11.2.0.2.0 driver and it seems there is a memory leak. Based on heap dump it seem that leek i near oracle.jdbc.xa.OracleXAResource$XidListEntry. Admins are missing about 200MB on each server after 3 days.
Class Name | Objects | Shallow Heap | Retained Heap
oracle.jdbc.xa.OracleXAResource$XidListEntry| 2,378,575 | 57,085,800 | 171,257,016
Class Name | Objects | Shallow Heap | Retained Heap
weblogic.transaction.internal.XidImpl| 2,378,605 | 57,086,520 | 114,172,880
2,378,605 objects are really a lot :) and it about 114 MB of weblogic.transaction.internal.XidImpl objects
I found patch 8423655 but it is for older driver version. Does anybody have a similar experience? Any solution?
Thanks
Patrik

After a discussion with support we have found patch for the problem:
Document Titleoracle.jdbc.xa.OracleXAResource$XidListEntry Objects Leaking in JDBC Driver for WebLogic Server (WLS) (Doc ID 872258.1)
You were right the problem was on Weblogic site and also on driver side. In last JDBC driver it is already fixed so we have to upgrade just WLS part.
Thanks
Patrik

Similar Messages

IFS ALERT NOTICE FOR JDBC MEMORY LEAK FIX

IFS ALERT NOTICE FOR JDBC MEMORY LEAK FIX
Product and Version Affected:
Product: Oracle Internet File System
Product ID: 7
Version: 1.0
Description: There is a memory leak when retrieving or saving BLOBs through JDBC. IFS will appear to continue to increase in its memory consumption until the user runs out of swap space, and the machine stops functioning.
Platform Affected: Sun SPARC Solaris, Windows NT
Likelihood of Occurrence: Most iFS customers will notice this problem, since most will retrieve and store enough document content that they will notice the memory leak.
Symptoms:
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- Significant swapping of the operating system.
- The user sees real memory and total memory continue to increase without bound when using any iFS protocols to retrieve and store document content.
- The memory usage goes back to normal when the iFS protocols are stopped.
Solution: Get the JDBC 8.1.6.0.1 patch for Solaris or NT (the OCI component, for JDK 1.1). Install it on all machines where the iFS protocols are running. The patch may be obtained on http://technet.oracle.com/software/tech/java/sqlj_jdbc/software_index.htm (you have to be logged into technet).
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null

Moving to Top

Oracle/JDBC Memory Leak

I am using the Oracle 7 client with the JDBC driver for Java 2. I am also using the Sun jdk 1.3 SE. Every time I establish a connection to any Oracle database, there is a bit of memory that is lost and can not be reclaimed. A simple program that connects to the database via DriverManager.getConnection(), followed by Connection.close() inside a loop shows the memory gradually increasing. Is this a bug? If so, where is the patch?

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Memory Leak in my JDBC application.

Hi
I am experiencing a memory leak in a test application using the JDBC-ODBC bridge to access an MS Access DB.
I close the result set, statement and connection objects after each query. Even then the memory allocated to the process increases by about 20K after each query.
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Fred.

I am having the same problem using JDBC-ODBC bridge with the MS SQL server DB. Even after closing all of the objects as specified.
Sorry couldn't be of much help but check the following link
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Memory Leak in 8.1.6.0.1 JDBC/OCI for Solaris

Hello,
there is a memory leak in the 8.1.6.0.1 JDBC-OCI driver for solaris.
The leak causes your jvm to eat up all memory
if you reuse callable statements
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different values).
The thin driver has no such problem. Is
there any fix available ?

Ok. The code spans multiple classes and
most of it comes from a customized version
of the Enhydra Java Application server.
I have a class called "StandardDBConnection"
which caches CallableStatements and is a
wrapperclass for java.sql.DBConnection. The
interesting method here is "prepareCall":
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* cached, return that statement, otherwise prepare and save in the
* cache.
* @param sql The SQL statement to be called.
* @return a new CallableStatement object containing the
* pre-compiled SQL statement.
* @exception java.sql.SQLException If a database access error occurs
* statement.
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throws SQLException {
PreparedStatement preparedStmt;
logDebug ("Prepare call: " + sql);
validate();
preparedStmt = (PreparedStatement)preparedStmtCache.get(sql);
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if (preparedStmt instanceof CallableStatement) {
preparedStmt.clearParameters();
else {
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// replace it with a CallableStatement
if (preparedStmt != null) {
preparedStmt.close();
else if (preparedStmtCache.size() >= maxPreparedStmts) {
String key = (String)preparedStmtCache.keys().nextElement();
((PreparedStatement) preparedStmtCache.remove(key)).close();
preparedStmt = connection.prepareCall(sql);
preparedStmtCache.put(sql, preparedStmt);
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The statements get closed when I close the
connection:
boolean closeStmts = true;
// Close the prepared statements.
Enumeration e = preparedStmtCache.keys();
while (e.hasMoreElements() && closeStmts) {
String key = (String)e.nextElement();
try {
((PreparedStatement)
preparedStmtCache.remove(key)).close();
} catch (SQLException except) {
// Ignore errors, we maybe handling one.
closeStmts = false;
log.write(Logger.NOTICE,
"DBConnection[" + id + "]: " + url +
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In my classes using database queries I just
use the prepareCall method of DBConnection
and do not have to care about anything.
Works perfectly with the thin driver, but
as soon as I switch to oci... :-|
<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by JDBC Dev Team:
Soda, Rupper,
Do you mind posting some code that shows us what your code was doing when you notice this leak?
Thanks.<HR></BLOCKQUOTE>
null

Oracle JDBC Thin Driver Memory leak in scrollable result set

Hi,
I am using oracle 8.1.7 with oracle thin jdbc driver (classes12.zip) with jre 1.2.2. When I try to use the scrollable resultset and fetch records with the default fetch size, I run into memory leaks. When the records fetched are large(10000 records) over a period of access I get "outofmemory" error because of the leak. There is no use increasing the heap size as the leak is anyhow there.
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This thread is ancient and the original was about the 8.1.7 drivers. Please start a new thread. Be sure to include driver and database versions, stack traces, sample code and why you think there is a memory leak.
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Microsoft Jdbc driver for SQL Server memory leak

I'm using Microsoft Jdbc driver and see there's some leak after running application for a while. I'm sure that it's from Jdbc driver because I sitch to Jtds and the issue went away. My question is is there anybody knows which web sites talk about memory leak issue in Microsoft Jdbc driver for SQL Server?
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I'm using Microsoft Jdbc driver and see there's some leak after running application for a while. I'm sure that it's from Jdbc driver because I sitch to Jtds and the issue went away. My question is is there anybody knows which web sites talk about memory leak issue in Microsoft Jdbc driver for SQL Server?
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Memory Leak when TOMCAT connects to Oracle 10g RAC using JDBC Thin driver.

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If you're doing XA, we absolutely do not support
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Memory leak in Tomcat 5.5

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import java.sql.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.awt.Image;
import java.awt.Graphics2D;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import javax.swing.ImageIcon;
import com.sun.image.codec.jpeg.JPEGCodec;
import com.sun.image.codec.jpeg.JPEGImageEncoder;
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private String dbURL = "jdbc:mysql://localhost/webapp?";
private String userID = "javauser";
private String passwd = "javadude";
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public void init() throws ServletException {
//Process the HTTP Get request
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
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       String siteString = request.getParameterValues("s")[0];
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           response.setContentType("image/jpeg");
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           writePicture(out,siteString);
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               int maxDimension = Integer.parseInt(maxDim);
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               OutputStream out = response.getOutputStream();
               writeThumbnailPicture(out, siteString, maxDimension);
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        ex.printStackTrace();
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          if (rs.next()) {
              byte[] data = rs.getBytes("Picture");
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                  Image inImage = new ImageIcon(data).getImage();
                  BufferedImage outImage = new BufferedImage(inImage.getWidth(null),
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          stmt.close();
          dbConnection.close();
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           //which to paint on.
           BufferedImage outImage = new BufferedImage(scaledW, scaledH,
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    catch(Exception ex){
      ex.printStackTrace();
//Clean up resources
public void destroy() {
private void jbInit() throws Exception {
}

you can try this:
open your connection outside the function, and then pass it like as a parameter...
writePicture(OutputStream out, String siteID, Connection conn)
this can solve the problem because opening the connection inside the function spends a lot of memory...
Hope this can help you
Regards
Fernando

Memory leak in weblogic 6.0 sp2 oracle 8.1.7 thin driver

Hi,
     I have a simple client that opens a database connection, selects from
a table containing five rows of data (with four columns in each row)
and then closes all connections. On running this in a loop, I get the
following error after some time:
<Nov 28, 2001 5:57:40 PM GMT+06:00> <Error> <Adapter>
<OutOfMemoryError in
Adapter
java.lang.OutOfMemoryError
<<no stack trace available>>
>
<Nov 28, 2001 5:57:40 PM GMT+06:00> <Error> <Kernel> <ExecuteRequest
failed
java.lang.OutOfMemoryError
I am running with a heap size of 64 Mb. The java command that runs
the client is:
java -ms64m -mx64m -cp .:/opt/bea/wlserver6.0/lib/weblogic.jar
-Djava.naming.f
actory.initial=weblogic.jndi.WLInitialContextFactory
-Djava.naming.provider.url=
t3://garlic:7001 -verbose:gc Test
The following is the client code that opens the db connection and does
the select:
import java.util.*;
import java.sql.*;
import javax.naming.*;
import javax.sql.*;
public class Test {
private static final String strQuery = "SELECT * from tblPromotion";
public static void main(String argv[])
throws Exception
String ctxFactory     = System.getProperty
("java.naming.factory.initial");
String providerUrl     = System.getProperty
("java.naming.provider.url");
Properties jndiEnv          = System.getProperties ();
System.out.println ("ctxFactory : " + ctxFactory);
System.out.println ("ProviderURL : " + providerUrl);
Context ctx     = new InitialContext (jndiEnv);
for (int i=0; i <1000000; i++)
System.out.println("Running query for the "+i+" time");
Connection con = null;
Statement stmnt = null;
ResultSet rs     = null;
try
DataSource ds     = (DataSource) ctx.lookup
(System.getProperty("eaMDataStore", "jdbc/eaMarket"));
con = ds.getConnection ();
stmnt = con.createStatement();
rs = stmnt.executeQuery(strQuery);
while (rs.next ())
//System.out.print(".");
//System.out.println(".");
ds = null;
catch (java.sql.SQLException sqle)
System.out.println("SQL Exception : "+sqle.getMessage());
finally
try {
rs.close ();
rs = null;
//System.out.println("closed result set");
} catch (Exception e) {
System.out.println("Exception closing result set");
try {
stmnt.close ();
stmnt = null;
//System.out.println("closed statement");
} catch (Exception e) {
System.out.println("Exception closing result set");
try {
con.close();
con = null;
//System.out.println("closed connection");
} catch (Exception e) {
System.out.println("Exception closing connection");
I am using the Oracle 8.1.7 thin driver. Please let me know if this
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thanks,
rudy

Repost in JDBC section ... very serious issue but it may be due to Oracle or
to WL ... does it happen if you test inside WL itself?
How many iterations does it take to blow? How long? Does changing to a
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Peace,
Cameron Purdy
Tangosol Inc.
<< Tangosol Server: How Weblogic applications are customized >>
<< Download now from http://www.tangosol.com/download.jsp >>
"R.C." <[email protected]> wrote in message
news:[email protected]...
Hi,
I have a simple client that opens a database connection, selects from
a table containing five rows of data (with four columns in each row)
and then closes all connections. On running this in a loop, I get the
following error after some time:
<Nov 28, 2001 5:57:40 PM GMT+06:00> <Error> <Adapter>
<OutOfMemoryError in
Adapter
java.lang.OutOfMemoryError
<<no stack trace available>>
>
<Nov 28, 2001 5:57:40 PM GMT+06:00> <Error> <Kernel> <ExecuteRequest
failed
java.lang.OutOfMemoryError
I am running with a heap size of 64 Mb. The java command that runs
the client is:
java -ms64m -mx64m -cp .:/opt/bea/wlserver6.0/lib/weblogic.jar
-Djava.naming.f
actory.initial=weblogic.jndi.WLInitialContextFactory
-Djava.naming.provider.url=
t3://garlic:7001 -verbose:gc Test
The following is the client code that opens the db connection and does
the select:
import java.util.*;
import java.sql.*;
import javax.naming.*;
import javax.sql.*;
public class Test {
private static final String strQuery = "SELECT * from tblPromotion";
public static void main(String argv[])
throws Exception
String ctxFactory = System.getProperty
("java.naming.factory.initial");
String providerUrl = System.getProperty
("java.naming.provider.url");
Properties jndiEnv = System.getProperties ();
System.out.println ("ctxFactory : " + ctxFactory);
System.out.println ("ProviderURL : " + providerUrl);
Context ctx = new InitialContext (jndiEnv);
for (int i=0; i <1000000; i++)
System.out.println("Running query for the "+i+" time");
Connection con = null;
Statement stmnt = null;
ResultSet rs = null;
try
DataSource ds = (DataSource) ctx.lookup
(System.getProperty("eaMDataStore", "jdbc/eaMarket"));
con = ds.getConnection ();
stmnt = con.createStatement();
rs = stmnt.executeQuery(strQuery);
while (rs.next ())
//System.out.print(".");
//System.out.println(".");
ds = null;
catch (java.sql.SQLException sqle)
System.out.println("SQL Exception : "+sqle.getMessage());
finally
try {
rs.close ();
rs = null;
//System.out.println("closed result set");
} catch (Exception e) {
System.out.println("Exception closing result set");
try {
stmnt.close ();
stmnt = null;
//System.out.println("closed statement");
} catch (Exception e) {
System.out.println("Exception closing result set");
try {
con.close();
con = null;
//System.out.println("closed connection");
} catch (Exception e) {
System.out.println("Exception closing connection");
I am using the Oracle 8.1.7 thin driver. Please let me know if this
memory leak is a known issue or if its something I am doing.
thanks,
rudy

Oracle 8.1.5 Linux Memory Leak?

We have been running Oracle 8.1.5 Server and Client on Redhat 6.1
kernel 2.2.12-20
glibc-2.1.2-11
Blackdown's JDK 1.2 RC3
We are having bad memory leaks and we have verified that they are
not in our source code using a memory profiler for Java-linux.
We are using the JDBC calls and the OCI JDBC driver.
We think that the memory leak is in libocijdbc8.so but we're not
sure. It could also be in glibc but the 2.1.2-11 version should
be pretty stable. It could also be in the Blackdown jvm.
Anyone have any ideas?
null

Oracle8iR2's JDBC works fine with Oracle8.1.5.
You can download the new JDBC driver.
null

Memory leak in "Tenured Generation" heap (JVM 1.5)?!

For about over a year, I'm trying to hunt down the memory leak in our server application. But after all the improvements I've made (especially with 'forgotten' listeners that didn't exist anymore), I'm confident that the application doesn't have a memory leak anymore. At least the new "jconsole.exe" tool of JDK 1.5 shows me a very intersting behaviour:
Even if the server app is doing nothing than one thread polling a database table for possible new jobs to process, the memory slightly increases over time ... very slightly. It's just like the screenshot at
http://java.sun.com/j2se/1.5.0/docs/guide/management/jconsole.html#memory
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Of course the thread loop creates objects but it doesn't hold any (debugged it several times and it is quite easy code). So this behaviour makes sense. But it doesn't make sense that the memory usage overall slowly increases over many hours (ultimativaly leading to an OutOfmemoryError).
So far, I still thought, it must be a memory leak in my application. But then, I played with jConsole and noticed this: if I just display the Memory Pool "Eden Space", the jagged line always drops down to the same level, i.e. no memroy leak. The "Survivor Space" is also constant in average (no memory leak). But the "Tenured Generation" line shows this memroy leak behaviour (slowly increases). This space is described as:
Tenured Generation (heap): pool containing objects that have existed for some time in the survivor space.
So, I'm not so sure anymore if this memory must be in my application. Unfortunately, jConsole doesn't show some kind of object tree that can be browsed and I would see what kind of object (collection) increase.
I tried profiling my application, but the profiled app runs so slowly that it would need many days or weeks until it's possible to identify some bad objects.
Is there another way to identify such memory waisters?

Write a main() that does the polling in a tight loop 1000 times. Then System.gc(); Thread.sleep(1000); System.exit(). Run the thing with -Xrunhprof. Observe the "live bytes" and "live objs" columns in the generated java.hprof.txt file. Anything that strikes as suspicious? If every polling round leaks one object, there's likely to be 1000 (or N*1000) of something live. Make sure the leak is in the polling routine by running it 1,000,000 rounds and getting an OutOfMemory.

Memory leak in OCI while using AQ

There seems to be a serious memory leak in the OCI driver (9.2.0.1) when using a JAVA client to dequeue a database queue (Advanced Queuing).
Continuous dequeuing causes the heap memory to increase, and this memory never gets freed which leads me to suspect a memory leak in the OCI components (as the memory allocated for the JVM is constant). The heap memory increases by 3-4 MB after a dequeue of 1000 RAW messages,
Has anyone come across this problem before and if so are there any solutions? Changing to a thin driver is not a solution for me due to other requirements.
I'm using using Oracle client v9.2.0.1 libraries running on Solaris 8.
The source code for my JAVA test client is as below:
/* JAVA dequeue */
package com.ubsw.risk.pce.eventqueues.test;
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import java.sql.*;
import oracle.jdbc.*;
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Connection conn = null;
AQSession aq_sess = null;
try {
Class.forName("oracle.jdbc.driver.OracleDriver");
//Use OCI connection
conn = DriverManager.getConnection("jdbc:oracle:oci:@DB_NAME.world","user","password");
conn.setAutoCommit(false);
Class.forName("oracle.AQ.AQOracleDriver");
while(true) {
aq_sess = AQDriverManager.createAQSession(conn);
runTest(aq_sess);
aq_sess.close();
aq_sess = null;
System.gc();
} catch (Exception e) {
e.printStackTrace();
System.out.println(e.toString());
try {
if (aq_sess != null) {
aq_sess.close();
if (conn != null) {
conn.close();
} catch (SQLException sqle) {
public static void runTest(AQSession aq_sess) throws AQException, SQLException
AQQueueTable q_table;
AQQueue queue;
AQMessage message;
AQRawPayload raw_payload;
AQEnqueueOption enq_option;
String test_data = "new message";
AQDequeueOption deq_option;
byte[] b_array;
/* Get a handle to a queue - in aquser schema: */
queue = aq_sess.getQueue ("user", "raw_msg_queue");
System.out.println("Successful getQueue");
/* Creating a AQDequeueOption object with default options: */
deq_option = new AQDequeueOption();
/* Dequeue a message: */
message = queue.dequeue(deq_option);
System.out.println("Successful dequeue");
/* Retrieve raw data from the message: */
raw_payload = message.getRawPayload();
b_array = raw_payload.getBytes();
System.out.println("bytes:" + b_array.toString());
queue.close();
((AQOracleSession)aq_sess).getDBConnection().commit();

This sounds very similar to the memory leak I have in Oracle 9i using Pro*C++. Everytime a connect is made memory appears to leak and it only happens in multithreaded mode not default mode. There is a thread about this under the Oracle C++ call interface. Under 9i it appears to leak about 60K per connect rather than 60 bytes.
Paul

Memory leak and char[] ?

Hello all,
I'm not sure whether this post should be here or in WebLogic section, so correct me if I'm wrong.
I'm working on JDeveloper 11.1.1.3 while deployments are made on standalone WebLogic 10.3.3. This thing occurred in previous versions also.
With every deployment WebLogic increases it's used memory until the famous PermGen space error, which is after about 5-6 deployments.
I'm doing my best to understand how to use memleak detection tools. I've switched JDev and WL from Sun jdk which was used before to JRockit, same thing happens. Both JDev's memory profiler and JRockit mission control show something that I really do not understand. char[] uses around 30% of heap space and keeps growing with deployments, next is String with 8%. I never use char in app.
Am I looking at the wrong thing? Is it normal for char[] to increase on WebLogic on deployments? Does anyone know how to check other things and what to check? Someone on other forums mentioned it would be useful to check if ApplicationContext keeps initializing over again on deployments. Does anyone know how to check this?
One more thing, I have successfully deployed app on Tomcat, and Tomcat said there is a memory leak in app, but could not tell anything specific.
I'm kinda lost in this :(

It is normal for the PermGen space of the Sun's JVM to get filled after several re-deployments. PermGen stands for "permanent generational". This space is used by classes that is unlikely to need to be garbage-collected, so they are placed in this memory space that is never garbage-collected (for example, the Class instances). When you redeploy an application, a new class loader instance is used and it instantiates new Class instances that fill up the PermGen space. But why this happens on JRockit either, I could not explain.
We have experienced memory leaks related to classes and components that use native memory. For example, we have had significant memory leak when using Oracle's JDBC OCI driver. We were not able to solve this problem, so we switched to JDBC Thin driver (which is very performant and stable today comparing to some years ago). If you are using Oracle JRockit, you can monitor the overall memory usage by the following JRockit command executed at OS command line:
jrcmd <jrockit_pid> print_memusage>where <jrockit_pid> should be replaced by the JVM process ID.
If you suspect existence of native memory leaks, then have a look at the article Thanks for the memory for explanations about how Java uses native memory.
Dimitar

JDBC memory leak in 11.2.0.2.0 driver ?

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